ec_commands: more kerneldoc conversions
ec_commands: more kerneldoc conversions

It's not necessarily required that all structs be using kerneldoc, but
several of these are adequately documented and fit the same pattern of
conversions that were done upstream -- except that they currently only
exist in the EC sources. Let's convert preemptively.

BRANCH=none
BUG=chromium:621123
TEST=presubmits

Change-Id: I0922db83983ed03f9a02142606c425f0af6313d1
Signed-off-by: Brian Norris <67059238af8e1945c40edb274ce1d51ba595dbf3@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1330109

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec